Revit to Navisworks for Clash Detection

Workflow for Revit to Navisworks to utilize Clash Detective tool

Research Goal and Objectives

This workflow will take you through the process of exporting a Revit file to Navisworks to use clash detection. The clash detective tool in Navisworks is a very useful tool to use, and is a great way to use Navisworks and Revit for MEP, structural, or electrical coordination, as well as other trades.

Process

1. Begin with the main 3D view open
2. In the "Project Browser" toolbar on the left side of the screen, right-click on the 3D View named {3D} and select "Duplicate View" ; "Duplicate"
3. Open the duplicate view by double-clicking the new 3D View named "Copy of {3D}." Rename the view by right-clicking the view in the "Project Browser" toolbar. The file should be renamed "Walls" as this will now be a view consisting of only walls. To make the view only contain walls, right-click on the view in the "Project Browser" toolbar again and select properties. Click the "Edit" button located next to the "Visibility/Graphics Overrides" heading (Figure 1). This will open the overrides for the 3D View. Click the "All" button to highlight all categories and now click any check-mark, which will unselect all categories (Figure 2). Scroll down and click on "walls" to highlight only the "walls" category, and click the check-mark, making only walls present in the "Walls" 3D View. Click "OK" until you return through all properties boxes to the view and you will see that only walls remain in the view(Figure 3).

   Figure 1

   Figure 2

   Figure 3

4. Repeat Steps 2 & 3, creating duplicate views of the main 3D view, but instead of walls select only "Windows" or "Doors" or "Structural Columns" etc. This process is shown below (Figure 4) with windows, doors, roofs, structural columns, structural beams, and floors as separate views containing only their respective categories. (Structural Beams only is shown)

   Figure 4

5. Once all desired views are created, each view must be exported as a Navisworks file by opening each view and exporting it using steps 1-3 of the process found here (Revit to Navisworks) separately for each new view. You should name each view respectively when saving
6. When all Navisworks files are exported, they can now be opened in Navisworks. Begin by double-clicking on one of the saved files to open it in Navisworks. Perform a "Save As" to make the file a Navisworks File Set (.nwf)
7. Begin importing the other Navisworks files by going to "File" ; "Append" ; and selecting the next file you wish to import. This can also be done using the shortcut Ctrl+A
8. When all desired objects are loaded into Navisworks, begin by opening the "Clash Detective" tab on the left side of the screen and click the "select" tab within clash detective
9. You select what to check for clashes by selecting one set of objects from the left side, ex. Columns, and what those objects may clash with on the right side, ex. Floors, (Figure 5) and click start to run the clash detective. A number of clashes will be listed in the field next to "Found." (Note: You can select all on the left and all on the right which will show all clashes within the building, but for a more refined clash investigation it is wise to choose only a few from each side)

   Figure 5

10. Click on the "Results" tab located next to the "Select" tab. This displays the clashes found individually, and they can be viewed by clicking on each clash listed. Shown below (Figure 6) is just one clash found using the Clash Detective (highlighted in orange). Once a clash is found, return to the original Revit file, and resolve the clash.

    Figure 6

11. When the clash is resolved, re-export the 3D views which may have changed to Navisworks by simply over-writing the original file (in this case the floor was edited and changed to resolve the clash)
12. Re-import the changed 3D View by right-clicking the category in the "Select" tab and selecting "Import Current Selection." Run the Clash Detective again and the clash should now be resolved, or no longer highlighted (Figure 7)

    Figure 7

13. Repeat this process for other clashes which need to be resolved.

Lessons Learned

• It is essential to export each separate view from Revit to Navisworks when utilizing clash detection tools to ensure ease of use within Navisworks. This also allows separate parameters to be highlighted when running the clash detection so that only certain clashes appear, and not all of them
• There are often times some clashes that appear that may not be a problem. Many of these clashes are instances of beams not being correctly joined to a column, or many other slight errors. If these clashes are found, they can be simply ignored, changed or adjusted and reloaded into Navisworks, or overridden within Navisworks by selecting "Resolve" under the "Status" of a particular clash in the "Report" tab

References

Autodesk Revit Architecture 2009
Autodesk Revit Structures 2009
Autodesk Navisworks Manage 2009

Acknowledgments

Dr. John Messner
Associate Professor of Architectural Engineering, CM Option

Ralph Kreider
Teaching Assistant